Hoist mechanism



Jan. 19, 1932. n. KENDALL ET AL HOIST MECHANISM Filed Aug. 14, 1928 3Sheets-Sheet INVENTOR.

Mafl, 07% a M Jan. 19, 1932. D. KENDALL ETAL HOIST MECHANI SM Filed Aug.14, 1928 3 Sheets-Sheet 2 IN V EN TOR. {M

Jan. 19, 1932 KENDALL E AL 1,841,958

HOIST MECHANISM Filed Aug. 14, 1928 5 Sheets-Sheet 5 IN V EN TOR.

Patented, Jan. 19, 1932 UNITED STATES PATENT OFFICE DAVID KENDALL ANDWALTER D. KELLER, OF ALLIANCE, OHIO, ASSIGNORS TO THE ALLIANCE MACHINECOMPANY, OF ALLIANCE, OHIO, A CORPORATION OF OHIO HOIST MECHANISMApplication filed August 14, 1928. Serial No. 299,483.

The present invention relates broadly to the art of material handling,and more particularly to mechanism for hoisting. For ex ample, theinvention is of great value in ladle cranes for handling hot metal.

It is customary in many hoisting installations to provide a plurality ofhoist cables, each of which is separably secured to a hoist drum at oneend and to the lifting hook at its opposite end. It not infrequentlyhappens that one of such cables breaks during a lifting operation, andprecipitates the load being lifted. In the event the mechanism is beingutilized for the lifting of molten metal, the breaking of one of thecables is apt to result in the dropping of the ladle and the spilling ofthe molten metal, with great danger of injury to workmen, and damage toequipment. The hazards with other types of equipment and other materialsis, in many cases, almost as great.

The present invention relates to an improved form of hoist mechanismembodying a plurality of hoist cables and of such construction that thebreaking of one of the cables does not result in dropping of the load orin the throwing of any sudden and violent shock on to the remainingcables.

In the accompanying drawings, there are shown for purposes ofillustration only certain preferred embodiments of the presentinvention, it being understood that the drawings do not define thelimits of our invention, as changes in the construction and arrangementof the parts, as well as in the exact location and arrangement of thepulleys and drums, may be made without departing from the spirit of ourinvention or the scope of our broader claims.

In the drawings:

Figure 1 is a perspective view, largely diagrammatic, illustrating oneembodiment of the present invention;

Figure 2 is a side elevational view of a host mechanism similar to thatshown in Figure 1;

Figure 3 is an end elevational view of the construction shown in Figure2;

Figure a is an elevational view, on an enlarged scale, of thecompensating mechanism; and

other lifting drum is a second pair of cables B. All of these cablespass downwardly from the lifting drums around pulleys 3 carried on axles4 journaled in supports 5 on a hoist head 6. From the pulleys 3 thecables pass upwardly around pulleys 7 supported in the crane structure,and thence extend clownwardly to a compensating mechanism.

The compensating mechanism comprises a lever or connector 8 for eachpair of cables connected through a central pivot 9 with am yoke orcarrier 10 making pivotal connections llwith links 12. The links 12, inturn, make a pivotal connection 13 with the sup ports 5. The axes of thepivots 13 are substantially normal to the axes of the pivots throughwhich the lever 8 is connected to the lever 10, whereby a substantiallyuniversal rocking movement of the yoke is permitted.

The yoke 10 carries a pair of spaced bolts let extending upwardlythrough openings in I the lever 8. The bolts let carry compressionsprings or shock absorbing means 15, the degree of compression of whichmay be variably adjusted by nuts 16. By reason of this construction, anyunequality in the respective pairs of cables A. or B is automaticallycompensated for by a variable compression of the springs 15 cooperatingwith the lever 8 to which the ends of the cables are connected. In thismanner any slight difference in the length of the respective cables doesnot re lieve any of the cables from carrying its proportionate load.

In the event that one of the cables of either pair breaks, the remainingcable of such pair immediately takes the full load, thereby causing itsspring 15 to be compressed to the limit. The load, however, is uniformlytransmitted to the hoist head 6 through the yoke 10 and its connectionsthereto. In the event of such a break, the springs 15 cushion the shockon the remaining cables, whereby the liability of breakage thereof underthe sudden imposition of the additional load is obviated.

The Figures 2, 3, 4 and 5 of the drawings show in detail a commercialembodiment of the invention, the parts in these figures of the drawingscorresponding to the parts heretofore described being designated withthe same reference characters but having a prime aflixed thereto. Asshown in these figures, the axles 4' each carry a plurality of pulleys3' around which the cables pass in the desired sequence. There is alsoprovided the required number of pulleys 7 for cooperation therewith.

As illustrated in detail more particularly in Figures 4 and 5, thelevers 8 comprise spaced links which receive therebetween the upper endof a link 17 carrying the pivot pin 9. The lower end of the link 17extends between spaced arms forming the yoke 10' and has a pivotalconnection 18 therewith. The bolts 14' are provided with eyes 19 attheir lower ends cooperating with pivot pins 20, these bolts passingthrough blocks 21 having trunnions 22 which make pivotal connection withthe levers 8'. The springs lie between the blocks 21 and the nuts 16'. Acertain amount of clearance is provided so that the springs 15' do notact unless a cable breaks. The cables are formed with eyes 23 for thereception of pins 24 in the tension links 25. which links make pivotalconnection 26 with the levers 8'.

A construction of the character described possesses the advantages ofeffecting a uniform distribution of the load between a phlralitv ofindependent cables and an article to be lifted. and possesses thefurther advantages of automatically compensating for any inequalities inor breakage of any of the cables without thereby imposing too severe orsudden a shock on the remaining cables. The compensating mechanism maytherefore be considered as a combined compensating and shock absorbingconstruction.

We claim:

1. Hoist mechanism, comprising a plurality of hoisting cables, aconnector joining the cables, a carrier pivoted to the connector, andshock absorbing means efl'ective between the connector and carrier.

2. Hoist mechanism, comprising a plurality of hoisting cables, aconnector joining the cables, a carrier flexibly attached to theconnector, and resilient means efi'ective between the connector andcarrier.

3. Hoist mechanism, comprising a plurality of hoisting cables, aconnector joining the cables, a carrier flexibly but permanentlyattached to the connector, and means 65 effective between the connectorand carrier

